Maximizing Recovery of Attic Oil from Highly-Fractured Crestal Area Using Horizontal Skimmers: A Case Study

Abstract

Abstract This paper presents the re-development strategy employed to recover attic oil from the highly-fractured crestal area of a carbonate reservoir. Optimum re-development strategies for the crestal area, along with planning and execution incorporating Best in Class (BiC) reservoir management practices are discussed. The crestal area was previously developed using full penetration vertical wells. After many years of continuous production and nearby injection, oil production rates in these crestal wells have declined with increasing water cut. The re-development strategy has been tailored to exploit this challenging opportunity and to maximize the production efficiently with selective placement of horizontal skimmer wells at the very top of the structure. Fit-for-purpose completion technologies were deployed to address the effects of the extensive fractures. Tapping oil continuously flowing into the crestal area by displacement, gravity, and capillary mechanisms, this re-development strategy has resulted in efficient and sustainable production.